2 * Unaligned memory access handler
4 * Copyright (C) 2001 Randolph Chung <tausq@debian.org>
5 * Significantly tweaked by LaMont Jones <lamont@debian.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2, or (at your option)
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 #include <linux/config.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <asm/uaccess.h>
28 /* #define DEBUG_UNALIGNED 1 */
30 #ifdef DEBUG_UNALIGNED
31 #define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __FUNCTION__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
33 #define DPRINTF(fmt, args...)
42 #define FIXUP_BRANCH(lbl) \
43 "\tldil L%%" #lbl ", %%r1\n" \
44 "\tldo R%%" #lbl "(%%r1), %%r1\n" \
47 /* 1111 1100 0000 0000 0001 0011 1100 0000 */
48 #define OPCODE1(a,b,c) ((a)<<26|(b)<<12|(c)<<6)
49 #define OPCODE2(a,b) ((a)<<26|(b)<<1)
50 #define OPCODE3(a,b) ((a)<<26|(b)<<2)
51 #define OPCODE4(a) ((a)<<26)
52 #define OPCODE1_MASK OPCODE1(0x3f,1,0xf)
53 #define OPCODE2_MASK OPCODE2(0x3f,1)
54 #define OPCODE3_MASK OPCODE3(0x3f,1)
55 #define OPCODE4_MASK OPCODE4(0x3f)
57 /* skip LDB - never unaligned (index) */
58 #define OPCODE_LDH_I OPCODE1(0x03,0,0x1)
59 #define OPCODE_LDW_I OPCODE1(0x03,0,0x2)
60 #define OPCODE_LDD_I OPCODE1(0x03,0,0x3)
61 #define OPCODE_LDDA_I OPCODE1(0x03,0,0x4)
62 #define OPCODE_LDCD_I OPCODE1(0x03,0,0x5)
63 #define OPCODE_LDWA_I OPCODE1(0x03,0,0x6)
64 #define OPCODE_LDCW_I OPCODE1(0x03,0,0x7)
65 /* skip LDB - never unaligned (short) */
66 #define OPCODE_LDH_S OPCODE1(0x03,1,0x1)
67 #define OPCODE_LDW_S OPCODE1(0x03,1,0x2)
68 #define OPCODE_LDD_S OPCODE1(0x03,1,0x3)
69 #define OPCODE_LDDA_S OPCODE1(0x03,1,0x4)
70 #define OPCODE_LDCD_S OPCODE1(0x03,1,0x5)
71 #define OPCODE_LDWA_S OPCODE1(0x03,1,0x6)
72 #define OPCODE_LDCW_S OPCODE1(0x03,1,0x7)
73 /* skip STB - never unaligned */
74 #define OPCODE_STH OPCODE1(0x03,1,0x9)
75 #define OPCODE_STW OPCODE1(0x03,1,0xa)
76 #define OPCODE_STD OPCODE1(0x03,1,0xb)
77 /* skip STBY - never unaligned */
78 /* skip STDBY - never unaligned */
79 #define OPCODE_STWA OPCODE1(0x03,1,0xe)
80 #define OPCODE_STDA OPCODE1(0x03,1,0xf)
82 #define OPCODE_FLDWX OPCODE1(0x09,0,0x0)
83 #define OPCODE_FLDWXR OPCODE1(0x09,0,0x1)
84 #define OPCODE_FSTWX OPCODE1(0x09,0,0x8)
85 #define OPCODE_FSTWXR OPCODE1(0x09,0,0x9)
86 #define OPCODE_FLDWS OPCODE1(0x09,1,0x0)
87 #define OPCODE_FLDWSR OPCODE1(0x09,1,0x1)
88 #define OPCODE_FSTWS OPCODE1(0x09,1,0x8)
89 #define OPCODE_FSTWSR OPCODE1(0x09,1,0x9)
90 #define OPCODE_FLDDX OPCODE1(0x0b,0,0x0)
91 #define OPCODE_FSTDX OPCODE1(0x0b,0,0x8)
92 #define OPCODE_FLDDS OPCODE1(0x0b,1,0x0)
93 #define OPCODE_FSTDS OPCODE1(0x0b,1,0x8)
95 #define OPCODE_LDD_L OPCODE2(0x14,0)
96 #define OPCODE_FLDD_L OPCODE2(0x14,1)
97 #define OPCODE_STD_L OPCODE2(0x1c,0)
98 #define OPCODE_FSTD_L OPCODE2(0x1c,1)
100 #define OPCODE_LDW_M OPCODE3(0x17,1)
101 #define OPCODE_FLDW_L OPCODE3(0x17,0)
102 #define OPCODE_FSTW_L OPCODE3(0x1f,0)
103 #define OPCODE_STW_M OPCODE3(0x1f,1)
105 #define OPCODE_LDH_L OPCODE4(0x11)
106 #define OPCODE_LDW_L OPCODE4(0x12)
107 #define OPCODE_LDWM OPCODE4(0x13)
108 #define OPCODE_STH_L OPCODE4(0x19)
109 #define OPCODE_STW_L OPCODE4(0x1A)
110 #define OPCODE_STWM OPCODE4(0x1B)
112 #define MAJOR_OP(i) (((i)>>26)&0x3f)
113 #define R1(i) (((i)>>21)&0x1f)
114 #define R2(i) (((i)>>16)&0x1f)
115 #define R3(i) ((i)&0x1f)
116 #define FR3(i) ((((i)<<1)&0x1f)|(((i)>>6)&1))
117 #define IM(i,n) (((i)>>1&((1<<(n-1))-1))|((i)&1?((0-1L)<<(n-1)):0))
118 #define IM5_2(i) IM((i)>>16,5)
119 #define IM5_3(i) IM((i),5)
120 #define IM14(i) IM((i),14)
122 #define ERR_NOTHANDLED -1
123 #define ERR_PAGEFAULT -2
125 int unaligned_enabled
= 1;
127 void die_if_kernel (char *str
, struct pt_regs
*regs
, long err
);
129 static int emulate_ldh(struct pt_regs
*regs
, int toreg
)
131 unsigned long saddr
= regs
->ior
;
132 unsigned long val
= 0;
135 DPRINTF("load " RFMT
":" RFMT
" to r%d for 2 bytes\n",
136 regs
->isr
, regs
->ior
, toreg
);
138 __asm__
__volatile__ (
140 "1: ldbs 0(%%sr1,%3), %%r20\n"
141 "2: ldbs 1(%%sr1,%3), %0\n"
142 " depw %%r20, 23, 24, %0\n"
145 " .section .fixup,\"ax\"\n"
149 " .section __ex_table,\"aw\"\n"
158 : "=r" (val
), "=r" (ret
)
159 : "0" (val
), "r" (saddr
), "r" (regs
->isr
)
162 DPRINTF("val = 0x" RFMT
"\n", val
);
165 regs
->gr
[toreg
] = val
;
170 static int emulate_ldw(struct pt_regs
*regs
, int toreg
, int flop
)
172 unsigned long saddr
= regs
->ior
;
173 unsigned long val
= 0;
176 DPRINTF("load " RFMT
":" RFMT
" to r%d for 4 bytes\n",
177 regs
->isr
, regs
->ior
, toreg
);
179 __asm__
__volatile__ (
180 " zdep %3,28,2,%%r19\n" /* r19=(ofs&3)*8 */
182 " depw %%r0,31,2,%3\n"
183 "1: ldw 0(%%sr1,%3),%0\n"
184 "2: ldw 4(%%sr1,%3),%%r20\n"
185 " subi 32,%%r19,%%r19\n"
187 " vshd %0,%%r20,%0\n"
190 " .section .fixup,\"ax\"\n"
194 " .section __ex_table,\"aw\"\n"
203 : "=r" (val
), "=r" (ret
)
204 : "0" (val
), "r" (saddr
), "r" (regs
->isr
)
207 DPRINTF("val = 0x" RFMT
"\n", val
);
210 ((__u32
*)(regs
->fr
))[toreg
] = val
;
212 regs
->gr
[toreg
] = val
;
216 static int emulate_ldd(struct pt_regs
*regs
, int toreg
, int flop
)
218 unsigned long saddr
= regs
->ior
;
222 DPRINTF("load " RFMT
":" RFMT
" to r%d for 8 bytes\n",
223 regs
->isr
, regs
->ior
, toreg
);
230 __asm__
__volatile__ (
231 " depd,z %3,60,3,%%r19\n" /* r19=(ofs&7)*8 */
233 " depd %%r0,63,3,%3\n"
234 "1: ldd 0(%%sr1,%3),%0\n"
235 "2: ldd 8(%%sr1,%3),%%r20\n"
236 " subi 64,%%r19,%%r19\n"
238 " shrpd %0,%%r20,%%sar,%0\n"
241 " .section .fixup,\"ax\"\n"
245 " .section __ex_table,\"aw\"\n"
254 : "=r" (val
), "=r" (ret
)
255 : "0" (val
), "r" (saddr
), "r" (regs
->isr
)
259 unsigned long valh
=0,vall
=0;
260 __asm__
__volatile__ (
261 " zdep %5,29,2,%%r19\n" /* r19=(ofs&3)*8 */
263 " dep %%r0,31,2,%5\n"
264 "1: ldw 0(%%sr1,%5),%0\n"
265 "2: ldw 4(%%sr1,%5),%1\n"
266 "3: ldw 8(%%sr1,%5),%%r20\n"
267 " subi 32,%%r19,%%r19\n"
270 " vshd %1,%%r20,%1\n"
273 " .section .fixup,\"ax\"\n"
277 " .section __ex_table,\"aw\"\n"
288 : "=r" (valh
), "=r" (vall
), "=r" (ret
)
289 : "0" (valh
), "1" (vall
), "r" (saddr
), "r" (regs
->isr
)
291 val
=((__u64
)valh
<<32)|(__u64
)vall
;
295 DPRINTF("val = 0x%llx\n", val
);
298 regs
->fr
[toreg
] = val
;
300 regs
->gr
[toreg
] = val
;
305 static int emulate_sth(struct pt_regs
*regs
, int frreg
)
307 unsigned long val
= regs
->gr
[frreg
];
313 DPRINTF("store r%d (0x" RFMT
") to " RFMT
":" RFMT
" for 2 bytes\n", frreg
,
314 val
, regs
->isr
, regs
->ior
);
316 __asm__
__volatile__ (
318 " extrw,u %1, 23, 8, %%r19\n"
319 "1: stb %1, 1(%%sr1, %2)\n"
320 "2: stb %%r19, 0(%%sr1, %2)\n"
323 " .section .fixup,\"ax\"\n"
327 " .section __ex_table,\"aw\"\n"
337 : "r" (val
), "r" (regs
->ior
), "r" (regs
->isr
)
343 static int emulate_stw(struct pt_regs
*regs
, int frreg
, int flop
)
349 val
= ((__u32
*)(regs
->fr
))[frreg
];
351 val
= regs
->gr
[frreg
];
355 DPRINTF("store r%d (0x" RFMT
") to " RFMT
":" RFMT
" for 4 bytes\n", frreg
,
356 val
, regs
->isr
, regs
->ior
);
359 __asm__
__volatile__ (
361 " zdep %2, 28, 2, %%r19\n"
362 " dep %%r0, 31, 2, %2\n"
364 " depwi,z -2, %%sar, 32, %%r19\n"
365 "1: ldw 0(%%sr1,%2),%%r20\n"
366 "2: ldw 4(%%sr1,%2),%%r21\n"
367 " vshd %%r0, %1, %%r22\n"
368 " vshd %1, %%r0, %%r1\n"
369 " and %%r20, %%r19, %%r20\n"
370 " andcm %%r21, %%r19, %%r21\n"
371 " or %%r22, %%r20, %%r20\n"
372 " or %%r1, %%r21, %%r21\n"
373 " stw %%r20,0(%%sr1,%2)\n"
374 " stw %%r21,4(%%sr1,%2)\n"
377 " .section .fixup,\"ax\"\n"
381 " .section __ex_table,\"aw\"\n"
391 : "r" (val
), "r" (regs
->ior
), "r" (regs
->isr
)
392 : "r19", "r20", "r21", "r22", "r1" );
396 static int emulate_std(struct pt_regs
*regs
, int frreg
, int flop
)
402 val
= regs
->fr
[frreg
];
404 val
= regs
->gr
[frreg
];
408 DPRINTF("store r%d (0x%016llx) to " RFMT
":" RFMT
" for 8 bytes\n", frreg
,
409 val
, regs
->isr
, regs
->ior
);
416 __asm__
__volatile__ (
418 " depd,z %2, 60, 3, %%r19\n"
419 " depd %%r0, 63, 3, %2\n"
421 " depdi,z -2, %%sar, 64, %%r19\n"
422 "1: ldd 0(%%sr1,%2),%%r20\n"
423 "2: ldd 8(%%sr1,%2),%%r21\n"
424 " shrpd %%r0, %1, %%sar, %%r22\n"
425 " shrpd %1, %%r0, %%sar, %%r1\n"
426 " and %%r20, %%r19, %%r20\n"
427 " andcm %%r21, %%r19, %%r21\n"
428 " or %%r22, %%r20, %%r20\n"
429 " or %%r1, %%r21, %%r21\n"
430 "3: std %%r20,0(%%sr1,%2)\n"
431 "4: std %%r21,8(%%sr1,%2)\n"
434 " .section .fixup,\"ax\"\n"
438 " .section __ex_table,\"aw\"\n"
452 : "r" (val
), "r" (regs
->ior
), "r" (regs
->isr
)
453 : "r19", "r20", "r21", "r22", "r1" );
456 unsigned long valh
=(val
>>32),vall
=(val
&0xffffffffl
);
457 __asm__
__volatile__ (
459 " zdep %2, 29, 2, %%r19\n"
460 " dep %%r0, 31, 2, %2\n"
462 " zvdepi -2, 32, %%r19\n"
463 "1: ldw 0(%%sr1,%3),%%r20\n"
464 "2: ldw 8(%%sr1,%3),%%r21\n"
465 " vshd %1, %2, %%r1\n"
466 " vshd %%r0, %1, %1\n"
467 " vshd %2, %%r0, %2\n"
468 " and %%r20, %%r19, %%r20\n"
469 " andcm %%r21, %%r19, %%r21\n"
470 " or %1, %%r20, %1\n"
471 " or %2, %%r21, %2\n"
472 "3: stw %1,0(%%sr1,%1)\n"
473 "4: stw %%r1,4(%%sr1,%3)\n"
474 "5: stw %2,8(%%sr1,%3)\n"
477 " .section .fixup,\"ax\"\n"
481 " .section __ex_table,\"aw\"\n"
497 : "r" (valh
), "r" (vall
), "r" (regs
->ior
), "r" (regs
->isr
)
498 : "r19", "r20", "r21", "r1" );
505 void handle_unaligned(struct pt_regs
*regs
)
507 static unsigned long unaligned_count
= 0;
508 static unsigned long last_time
= 0;
509 unsigned long newbase
= R1(regs
->iir
)?regs
->gr
[R1(regs
->iir
)]:0;
511 int ret
= ERR_NOTHANDLED
;
513 register int flop
=0; /* true if this is a flop */
515 /* log a message with pacing */
518 if (unaligned_count
> 5 && jiffies
- last_time
> 5*HZ
)
523 if (++unaligned_count
< 5)
526 sprintf(buf
, "%s(%d): unaligned access to 0x" RFMT
" at ip=0x" RFMT
"\n",
527 current
->comm
, current
->pid
, regs
->ior
, regs
->iaoq
[0]);
528 printk(KERN_WARNING
"%s", buf
);
529 #ifdef DEBUG_UNALIGNED
533 if (!unaligned_enabled
)
537 /* handle modification - OK, it's ugly, see the instruction manual */
538 switch (MAJOR_OP(regs
->iir
))
546 if (regs
->iir
&0x1000) /* short loads */
548 newbase
+= IM5_3(regs
->iir
);
550 newbase
+= IM5_2(regs
->iir
);
551 else if (regs
->iir
&0x2000) /* scaled indexed */
554 switch (regs
->iir
& OPCODE1_MASK
)
564 newbase
+= (R2(regs
->iir
)?regs
->gr
[R2(regs
->iir
)]:0)<<shift
;
565 } else /* simple indexed */
566 newbase
+= (R2(regs
->iir
)?regs
->gr
[R2(regs
->iir
)]:0);
572 newbase
+= IM14(regs
->iir
);
579 newbase
+= IM14(regs
->iir
&~0xe);
585 newbase
+= IM14(regs
->iir
&6);
592 newbase
+= IM14(regs
->iir
&~4);
597 /* TODO: make this cleaner... */
598 switch (regs
->iir
& OPCODE1_MASK
)
602 ret
= emulate_ldh(regs
, R3(regs
->iir
));
609 ret
= emulate_ldw(regs
, R3(regs
->iir
),0);
613 ret
= emulate_sth(regs
, R2(regs
->iir
));
618 ret
= emulate_stw(regs
, R2(regs
->iir
),0);
626 ret
= emulate_ldd(regs
, R3(regs
->iir
),0);
631 ret
= emulate_std(regs
, R2(regs
->iir
),0);
640 ret
= emulate_ldw(regs
,FR3(regs
->iir
),1);
646 ret
= emulate_ldd(regs
,R3(regs
->iir
),1);
654 ret
= emulate_stw(regs
,FR3(regs
->iir
),1);
660 ret
= emulate_std(regs
,R3(regs
->iir
),1);
667 ret
= ERR_NOTHANDLED
; /* "undefined", but lets kill them. */
671 switch (regs
->iir
& OPCODE2_MASK
)
675 ret
= emulate_ldd(regs
,R2(regs
->iir
),1);
679 ret
= emulate_std(regs
, R2(regs
->iir
),1);
684 ret
= emulate_ldd(regs
, R2(regs
->iir
),0);
687 ret
= emulate_std(regs
, R2(regs
->iir
),0);
692 switch (regs
->iir
& OPCODE3_MASK
)
696 ret
= emulate_ldw(regs
, R2(regs
->iir
),0);
699 ret
= emulate_ldw(regs
, R2(regs
->iir
),1);
704 ret
= emulate_stw(regs
, R2(regs
->iir
),1);
707 ret
= emulate_stw(regs
, R2(regs
->iir
),0);
710 switch (regs
->iir
& OPCODE4_MASK
)
713 ret
= emulate_ldh(regs
, R2(regs
->iir
));
717 ret
= emulate_ldw(regs
, R2(regs
->iir
),0);
720 ret
= emulate_sth(regs
, R2(regs
->iir
));
724 ret
= emulate_stw(regs
, R2(regs
->iir
),0);
728 if (modify
&& R1(regs
->iir
))
729 regs
->gr
[R1(regs
->iir
)] = newbase
;
732 if (ret
== ERR_NOTHANDLED
)
733 printk(KERN_CRIT
"Not-handled unaligned insn 0x%08lx\n", regs
->iir
);
735 DPRINTF("ret = %d\n", ret
);
739 printk(KERN_CRIT
"Unaligned handler failed, ret = %d\n", ret
);
740 die_if_kernel("Unaligned data reference", regs
, 28);
742 if (ret
== ERR_PAGEFAULT
)
744 si
.si_signo
= SIGSEGV
;
746 si
.si_code
= SEGV_MAPERR
;
747 si
.si_addr
= (void __user
*)regs
->ior
;
748 force_sig_info(SIGSEGV
, &si
, current
);
753 /* couldn't handle it ... */
754 si
.si_signo
= SIGBUS
;
756 si
.si_code
= BUS_ADRALN
;
757 si
.si_addr
= (void __user
*)regs
->ior
;
758 force_sig_info(SIGBUS
, &si
, current
);
764 /* else we handled it, let life go on. */
769 * NB: check_unaligned() is only used for PCXS processors right
770 * now, so we only check for PA1.1 encodings at this point.
774 check_unaligned(struct pt_regs
*regs
)
776 unsigned long align_mask
;
778 /* Get alignment mask */
781 switch (regs
->iir
& OPCODE1_MASK
) {
799 switch (regs
->iir
& OPCODE4_MASK
) {
814 return (int)(regs
->ior
& align_mask
);